1. Technical Field
Embodiments of the subject matter disclosed herein generally relate to methods and systems and, more particularly, to mechanisms and techniques for cleaning seismic equipment that is deployed in water or underwater.
2. Discussion of the Background
During the past years, interest in developing new oil and gas production fields has dramatically increased. However, the availability of land-based production fields is limited. Thus, the industry has now extended drilling to offshore locations, which appear to hold a vast amount of fossil fuel. Offshore drilling is an expensive process. Thus, those engaged in such a costly undertaking invest substantially in geophysical surveys to more accurately decide where to drill in order to avoid a dry well.
Marine seismic data acquisition and processing generate a profile (image) of the geophysical structure (subsurface) under the seafloor. This profile is used by those trained in the field to evaluate the presence or absence of oil and/or gas traps. Thus, providing a high-resolution image of the subsurface is an ongoing process for the exploration of natural resources, including, among others, oil and/or gas.
During a seismic gathering process, as shown in FIG. 1, a vessel 10 tows an array of seismic detectors provided on streamers 12. The streamers may be disposed horizontally, i.e., lying at a constant depth relative to a surface 14 of the ocean. The vessel 10 also tows a sound source assembly 16 that is configured to generate an acoustic wave 18. The acoustic wave 18 propagates downward, toward the seafloor 20, and penetrates the seafloor until eventually a reflecting structure 22 (reflector) reflects the acoustic wave. The reflected acoustic wave 24 propagates upward until it is detected by a detector on streamer 12.
The above-noted arrangement is towed underwater for days, if not weeks, for a given survey. Thus, it was noted that various marine animals, e.g., barnacles, attach to various components of the streamer, e.g., external skin, electronic components, birds, etc. The barnacles may change the desired weight of the streamer, may make the streamer deviate from its desired towed position, or simply may make it difficult to manipulate the streamer for maintenance or when deployed underwater.
Traditional methods employ a cleaning device configured to move along the streamer and clean the streamer of marine animals. However, there are problems with these devices because they are bulky and they need to travel along various elements (e.g., birds, electronic boxes, etc.) connected to the streamer. Accordingly, it would be desirable to provide systems and methods that avoid the afore-described problems and drawbacks.